DoubleTwist, the popular desktop and mobile alternative to iTunes, has just launched a social sharing feature which allows its users to post what they’re listening to on Facebook or Twitter. Alongside the message text, the post also includes a link that, when clicked, will take visitors to a custom webpage offering an artist bio, news, concert dates, and the corresponding music video.

These artist profile pages are powered by 7Digital and The Echo Nest, says DoubleTwist. (Incidentally, 7Digital is all over the news this week. It also just announced a partnership with RIM to power the BlackBerry 10 music store, as well as a $10 million infusion of capital.) Other content on these artist pages is sourced from Songkick, YouTube, and Last.fm. The “Buy” button, of course, takes you to 7Digital’s store.

You can see an example tweet here. Meanwhile, this (also pictured below) is what one of the artist profile pages looks like.

DoubleTwist notes that the sharing feature is entirely within the user’s control – there’s no automatic sharing, so you’ll be the saved the embarrassment of telling your friends that, yes, you’re still listening to Gangnam Style on repeat.